Photometric determination of phosphate. • DIN method: ammonium molybdate reacts with orthophosphate ions to form phosphomolybdic acid. This is reduced to molybdenum blue. For the determination of total phosphate, an acidic oxidation at 100 – 120 °C must preceed to detect poly- and organic phosphates. (Reaction basis according to DIN EN ISO 6878-D11). • REF: 985095 • Type: tube test 0-95 • Messbereich: 0,05 – 0,50 mg/L P (PO4-P); 0,2 - 1,5 mg/L PO43- • Sufficient for: 20 tests • Shelf life: at least 1 year after production • Sea water suitability: yes (ortho-P) • Occasional precipitations after the digestion can be filtered off with membrane filtration kit 0.45 µm (REF 916 50). In case of a high content of organic matter and/or organically bound phosphorus, we recommend digestion with NANOCOLOR® NanOx Metal (REF 918978). • Determination of total phosphorus with NANOCOLOR® NanOx Metall: For phosphorus compounds which are difficult to oxidize, we recommend digestion with NANOCOLOR® NanOx Metal (REF 918978).